This invention relates to electrical connectors, and more particular to electrical connectors for coupling circuits on printed circuit boards.
Many computing devices, such as desktop computers, workstations, main-frame and super-computers employ multiple printed circuit boards (xe2x80x9cPCBxe2x80x9d) that include various microprocessors, printed circuits and other components that must be electrically coupled together to transmit data and/or power. The electrical traces on one or more layers of the PCB form the printed circuits and typically terminate in one or more terminals or contacts for making connections. Every decreasing element sizes, such a pitch (i.e., the spacing between successive components), width, and height, exacerbate the problem of providing secure and reliable connections between the printed circuits. Precise positioning on the order of thousandths of an inch is often necessary. Consistent pressure across each of the many contacts is also desirable to assure a reliable connection. A single failed or intermittent connection can result in large amounts of xe2x80x9cdown-timexe2x80x9d for the computing device, and costly troubleshooting by highly skilled technicians.
Highly parallel processing super-computers present a particularly significant problem in terms of space constraints. Super computers rely on a high number of connections between circuit boards that each carry one or more microprocessors. The nature of parallel processing places high demands on the timing of signals, including clock signals across the various computer components. The PCBs are spaced relatively close together to reduce the length of the connections between the PCBs in an effort to improve the timing of the signals. The tight spacing hinders the ability of technicians to access particular computer components, such as the PCBs and electrical connectors. This presents a particular problem to computer manufacturers and owners who desire a modular design that permits failed components to be quickly and easily replaced. If serviceable, a modular design would also permit the addition of new or additional processors as desired, for example when more processing power is required or when the processors become more affordable. This could significantly extend the life of the computing device.
According to principles of the present invention, a clamp for an electrical connector to a printed circuit board is structured to provide quick and accurate connection.
The electrical connector is positioned inside the clamp and has electrodes organized in a pattern for contact with the printed circuit board. The clamping assembly which holds the electrical connector has alignment members to ensure precise and accurate alignment with the printed circuit board. In order to provide quick attachment and release, the clamp assembly has three positions during the clamping and unclamping sequence. In a first position, the clamp is fully open and the electrical connector is held in the position so that it may be placed over a printed circuit board in preparation for attachment. In a second configuration, the clamping assembly is clipped into a preloaded position to properly align the electrical connectors and hold the clamping assembly into position for final attachment. In the third, final attachment stage, the clamping assembly is solidly connected to the printed circuit board with rigid bolts extending through the clamp assembly, through the printed circuit board and to a clamping member in the clamp assembly so as to hold the electrodes on the electrical connectors in complete electrical contact with the electrodes on the printed circuit board.
The clamp assembly may be easily attached and removed from the printed circuit board with high reliability. All electrical connections between electrodes will be properly made and that it can be quickly removed without damage to the electrical contacts.